I agree with Blackcat.
I have a varied group with 3 infants. Honestly, pick ups are never an issue with the infants. I like to have a general idea so they can be "ready" -fed a bottle, not ready to have a bottle, check their bottoms one more time etc. But, if a mom shows up- I will say last bottle was________, let me make sure they are dry and ready to go in the carseat. And if I have just made them a bottle- I will hand it to parent and say well you better have a seat and feed them this or you will have a long drive home!
Parents see my house as it really is... chaos some days. It is ok. Infants are not disturbed by pick ups... the older ones sometimes get wound up.. that is life.
time frame is just that. Today baby and 2 yo will be picked up between 3:30 and 4:15. Baby last ate 11:30 so he should be ready to eat in a bit so he will be fine for that pick up time. Snack for 2yo is at 3:00 so she will be good to go. I will be sure she pees after snack
My knowing they are coming is more for the parent's convience than mine.
It is still strange to me.